Many containers to store beverage, canned fruits and vegetables, paints and the like were and are still today made of aluminum or tinplate. These containers are built to rigid enough to withstand a certain amount of stacking and rough handling during shipping. With the rise of the prices of metals the industry has turn to less expensive materials such as plastics and paperboard.
Composite containers that include a layer of paperboard or other paper substrate held within metal ends have been used for packaging a wide variety of viscous, semi-solid or solid materials, such as paints, snacks, powders, foods, beverages and other perishable items.
The inner surfaces of the paperboard in these composite containers is typically protected by coating the paperboard with a barrier layer of thermoplastic material, or by permanently attaching various UV light, oxygen and/or moisture barrier layers to the paperboard. The options of coating the paperboard body of the composite container with a barrier layer of thermoplastic material or adhesively securing various UV light, oxygen and moisture barrier layers to the paperboard to avoid certain of the drawbacks of using plastic bags discussed above, however, the paperboard would require an expensive hydra-pulping process in order to separate the paper and plastic components. Many jurisdictions also charge a recycling fee for using such plastic coated containers which require an additional step in order to be fully broken down into components that can be individually recycled.
For certain applications such as paint cans, it has also been taught to insert a plastic bag to protect the interior surface of the container such as in U.S. Pat. No. 4,298,134. This technique has the advantage of generally being easy to disassemble from the container. Some of the drawbacks of using plastic bags are that they don't generally conform to the full perimeter of the container and can result in undesired air pocket between the plastic bag and the wall of the container or bunching, folding over, tearing of the plastic bag inside the container. The composite container may also be difficult or impractical to disassemble into its components if the bottom of the bag is adhesively secured to the metal or plastic base of the container.
A further problem generally with composite containers is that one or more of the metal or plastic end pieces remain attached in whole or in part to the paperboard body after the container is opened. The complete disassembly of the composite container into components that can be individual recycled is therefore not possible or can be a difficult or tedious task to accomplish by the consumer.
Accordingly, it would be desirable to provide a low cost composite container and a method for manufacturing such a container which can be easily broken down and separated into material groups that require separate recycling.
This background information is provided for the purpose of making known information believed by the applicant to be of possible relevance to the present invention. No admission is necessarily intended, nor should be construed, that any of the preceding information constitutes prior art against the present invention.